My 305 in my 86 blazer dd is dying so I decided to put the 350 out of my 79 project blazer in and build a 4 bolt main stroked small block for the project truck. The 350 is a jaspers crate engine that I originally ordered for my '71 chevelle and is currently connected to the TH350 in the '79. Now I know right around 86 was the crossover year for the 1 piece rear main seal and the external balancing. Will I be able to use the flywheel/pressure plate from the '86 305 or will I need to find one from an older vehicle. The 86 has a sm465 tranny.